I have long been an advocate that smokers should carry a little bag, like dog walkers, to clean up after themselves.  But I saw an even better idea on a comment thread recently.  That, like with bottles and cans, a recycling fee could be imposed and for every filter returned to a recycling center, whoever brought them in could get 5c a filter, or some amount that would pan out economically.  We don’t need any more taxes on cigarettes, but this special fee would help.  And I think Big Tobacco has enough money that it could figure out some constructive way of recycling all the used filters.  If the beverage industry can do it, so can these people.